Merging r300267:

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r300267 | tejohnson | 2017-04-13 17:51:49 -0400 (Thu, 13 Apr 2017) | 11 lines

[Support] Fix ErrorOr assertion when /proc/cpuinfo doesn't exist.

The ErrorOr should not be dereferenced on the error path.

Patch by Jacob Young

Reviewers: tejohnson

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D32032
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llvm-svn: 305264

llvm/lib/CodeGen/GlobalMerge.cpp

@@ -559,6 +559,10 @@ bool GlobalMerge::doInitialization(Module &M) {
     if (GV.isDeclaration() || GV.isThreadLocal() || GV.hasSection())
       continue;
 
+    // It's not safe to merge globals that may be preempted
+    if (TM && !TM->shouldAssumeDSOLocal(M, &GV))
+      continue;
+
     if (!(MergeExternalGlobals && GV.hasExternalLinkage()) &&
         !GV.hasInternalLinkage())
       continue;

llvm/lib/Support/Host.cpp

@@ -1232,6 +1232,7 @@ static int computeHostNumPhysicalCores() {
   if (std::error_code EC = Text.getError()) {
     llvm::errs() << "Can't read "
                  << "/proc/cpuinfo: " << EC.message() << "\n";
+    return -1;
   }
   SmallVector<StringRef, 8> strs;
   (*Text)->getBuffer().split(strs, "\n", /*MaxSplit=*/-1,

llvm/test/CodeGen/ARM/global-merge-external.ll

@@ -2,6 +2,7 @@
 ; RUN: llc < %s -mtriple=arm-eabi  -arm-global-merge -global-merge-on-external=true  | FileCheck %s --check-prefix=CHECK-MERGE
 ; RUN: llc < %s -mtriple=arm-eabi  -arm-global-merge -global-merge-on-external=false | FileCheck %s --check-prefix=CHECK-NO-MERGE
 ; RUN: llc < %s -mtriple=arm-macho -arm-global-merge                                 | FileCheck %s --check-prefix=CHECK-NO-MERGE
+; RUN: llc < %s -mtriple=arm-eabi  -arm-global-merge -relocation-model=pic           | FileCheck %s --check-prefix=CHECK-NO-MERGE
 
 @x = global i32 0, align 4
 @y = global i32 0, align 4